The speech therapy, as the health science that studies human communication, plays a major role both on the diagnosis and on the treatment of people with autism. However, there are only few speech therapists who make regular publications on the theme - revealing that this is an area where more studies need to be made. The autistic disorder is characterized by a developmental deficit on social interaction, communication and behavior. The diagnosis must be substantial and the three fields above are to be taken into account. Frequently, the speech therapist is the first professional the parents look for; thus, such professional must be able to identify those cases. The objective of this research was to assess methods and protocols of assessment and diagnosis of the autistic disorder, available in Brazilian literature, that could be applied to the clinical speech therapy. Based on several references, ten protocols were found: seven were translated and validated from a foreign language into Brazilian Portuguese and three were developed in Brazil. No Brazilian publications were found using four out of the ten instruments that aimed at screening or diagnosing suspected cases or under risk of autism. It is also clear the minor participation of the speech therapist in such process. Additionally, none of those instruments was considered accurate enough to diagnose such disorder. It is of major importance stressing the need of a critical point of view regarding the reality of things that still happen in the process of diagnosing autism.